The present invention refers to a protection cover for pipe bends produced from plastic by deep drawing and shaped by deformation to generally the shape obtained by cutting a comprehensive or complete isolation cover installed on a pipe bend along the interior generatrics line and bending apart and separating the two edges created by the cutting.
Such a protection cover when in a position of rest and before the cover is installed on a pipe bend resiliently maintains its shape which can be described as follows. The cover contains an elongated, cup-formed part, rounded in cross-section across the longitudinal direction and has a diameter that is essentially less than the outer generatrics diameter of the pipe bend. The cover further has at each short side a tail section or a part formed like a spiss gatt, but having the ends thereof bent inwardly; a spiss gatt being a canoe-shaped river dingy. The sides have an edge length such that when the protection cover is extended around a pipe bend, the diametrical plane or the transverse diameter of the cup-shaped part in the direction of the curvature plane of the pipe bend, the tail section or spiss gatt formed part will, under resilient or snap action, be drawn out to an edge line that is superimposed on the fictive cutting line along the interior generatrics line of the pipe bend mentioned above. The free edges of the aforedescribed pipe cover are thereby comprehensive and, in a position of rest before the cover is applied to a pipe bend, are positioned in the same level or plane.
The reason for wanting to apply such protection covers over pipe bends is that the pipes often contain either a very cold or a very hot flowing medium or fluid. Thus, the pipes must be insulated to prevent heat exchange with the surrounding environment so that the temperature of the fluid does not change. It has been customary to insulate pipes with some means of insulation material which usually has the shape of a pipe shell. The pipe shell may be made from mineral wool, or from expanded plastic, or from any other good insulation means. All of these insulation means, however, are strongly sensitive to exterior influence, such as susceptibility to damage.
Very often, these type pipes run along the roof or along the walls of narrow spaces, such as are found in basement passes, heater rooms, corridors, passages in vessels, and so forth. However, insulation applied to conduits and pipes in these type places is easily damaged, especially if heavy or clumsy objects are transported therethrough. For this reason, it is customary to surround the insulation with a protection cover of plastic or sheet metal.
Such protection covers may easily be applied on straight pipe parts, but there has been some difficulty in covering the pipe bends. For that reason, it has been proposed to use deep drawn protection covers as mentioned above.
For practical reasons, when deep drawing, it is normal to start from an even or uniform disc of plastic material from which the deep drawn object is produced. Consequently, the deep drawn object must be placed over an even frame, inside of which is a cavity and which is either subjected to air under pressure on one side of the plastic disc, or subjected to vacuum on the other side of the plastic disc. Thus, after the plastic disc has been heated to a plastic state and a differential in pressure is applied, the plastic disc is re-shaped to conform to the shape of the inner side of the frame's cavity. The consequence of this is that all deep drawn objects will be positioned with their upper comprehensive free ends in a single plane; that is, the plane in which one initially applied the plastic disc. If a protection cover for a pipe bend is arranged so that the free edge of the protection cover is comprehensive in the position of rest of the insulation cover in a single plane, one will avoid the necessity of cutting the work clean during the production of the protection cover. Although it is possible to do this, the protection covers formed thereby can only be used or adapted for a single pipe bend of a given dimension. The dimension of the pipe bend produced as described above is determined by the exterior diameter of the pipe proper and also by the bend radius of the pipe bend.
In practice in order to mount pipes in configurations based on the pipe run, it is necessary for each separate dimension of pipe to have pipe bends of different types, mutually separated by different curvature radius. If all of the pipe bend shapes are to be covered by a single pipe shell and a protection cover, then such a large assortment of protection covers is required that it is uneconomical to maintain and store a sufficient supply of each type.